Question----are you a "tweeker"? Just curious. I have used several styrofoam incubators and never had a heat spike unless I tweeked the electronic thermostat a little to try and raise the temp a speck---and it jumped way up. I do all or most all my tweeking before I put the eggs in. I read alot of people plug in their incubator for a day or two ahead-----get the temp right, open it and put their turner and eggs in----WRONG. The turner has a motor that gets warm---puts out some heat which effects the inside temp. Always put the turner in in the beginning----plugging both in. Now on day 18 when you take the turner out---seems with the electronic thermostat the heat drops a little----no turner motor heat now---I always have to tweek a speck to get the temp back right-----I do this and monitor it close for a few hours---then leave it alone----I have never had a problem. I have had real good hatches with them. I do NOT like these electronic thermostat that comes in alot of the cheaper ones I have, because they are so sensitive-----I rather have a wafer thermostat. I got a few styrofoam with the wafer thermostat and have used them many times----I just pull them out the box I store them in---plug them in and set the eggs when they are up to temp. RARELY ever having to touch/readjust the thermostat when it was stored from the last hatch. I rather have the wafer. My cabinet hatcher has the wafer----when I used it the first time I adjusted it to the right temp, used this hatcher every week for well over a year-----hatching 1000's and 1000's of eggs and have NEVER had to re-adjust the wafer thermostat and this hatcher is in a unheated/not cooled out building.
I like the thermostat I see on the Incuview, but I have never owned a incuview or a Brinsea.